Roughskin Dogfish

The Roughskin Dogfish is a deep-sea shark belonging to the family Somniosidae, characterized by a stout, cylindrical body covered in coarse, abrasive dermal denticles that give the species its common name. Like other members of its genus, it possesses two spineless dorsal fins, a subterminal mouth equipped with blade-like lower teeth suited for slicing prey, and large green-tinted eyes adapted to low-light conditions. As a slow-moving benthic and bathypelagic predator, it feeds opportunistically on fishes, cephalopods, and crustaceans, and likely plays a role as both predator and scavenger in deep-sea food webs, contributing to nutrient cycling in these poorly studied ecosystems.

This species has a remarkably wide, disjunct distribution across tropical and temperate oceans, recorded from New Zealand, Australia, Japan, Chile, Portugal, South Africa, Brazil, Mexico, the Bahamas, Mauritania, Madagascar, and numerous other coastal nations. It inhabits marine oceanic waters, typically along continental and insular slopes at considerable depths, reflecting its adaptation to deep, cold, high-pressure environments.

The primary threat to this species is ongoing fishing and harvesting of aquatic resources, particularly as bycatch in deepwater trawl and longline fisheries targeting other species. Its slow growth, late maturity, and low reproductive output—traits typical of deepwater sharks—limit its capacity to recover from fishing pressure.

Specific conservation measures targeting this species are limited, though it may benefit indirectly from deepwater fishery management and depth-restricted trawling regulations in some jurisdictions. Population trends remain unknown due to the difficulty of monitoring deep-sea species.

Given continued fishing pressure across much of its range and its low intrinsic resilience, the species' conservation outlook remains uncertain, warranting continued monitoring and inclusion in bycatch mitigation efforts.